Air-pump.



OMLlNSOw,

AIR PUMP.

APPLICATION FILED FEB. 65. 1917. 1 ,ZfiAQl Patented Nov. 6, 1917.

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25 an 7 3 Z4 lwuamtoz JOHN K. TOMLINSON, on nononvnnrn, wns'r VIRGINIA.

AIR-PUMP.

Specification of Letters Patent.

Patented Nov. 6, 191,7.

7 Application filed February 6, 1917. Serial No. 146,958.

To all whom it may concern:

Be it known that I, JOHN K. TQMLINSON,

a citizen of the United States, residing at Ronceverte, in the county ofGreenbrier and 5 State of WVest Virginia, have invented a new and usefulAir-Pump, of which the following is a specification.

This invention relates to air pumps particularly designed for use ininflating the tires of automobiles and the like, one of the objects ofthe invention being to provide a double cylinder pump so constructed asto avoid all leakage of air such as has heretofore occurred wherepacking glands have been used in connection with double cylinder pumps.

A further object is to provide a pump which is simple, durable andcompact and will not readily get out of order.

With the foregoing and other objects in View which will appear as thedescription proceeds, the invention resides in the combination andarrangement of parts and in the details of construction hereinafterdescribed and claimed, it being understood that changes in the preciseembodiment of the invention herein disclosed, .can be made within thescope of what is claimed," without departing from the spirit of theinvention.

In the accompanying drawings the preferred form of the invention hasbeen shown.

In said drawings v Figure 1 is a side elevation of a pump embodying thepresent improvements, the same being shown collapsed, as when not inuse.

Fig. 2 is an enlarged vertical longitudinal section through the pump andshowing the positions of the parts while in use.

Fig. 3 is an enlarged vertical section through the base of the pump,said section being taken on the line 33 Fig. 4.

Fig. 4 is a section on line 4-t Fig. 1.

Referring to the figures by characters of reference 1 designates a basehaving a socket 2 communicating through a passage 3 with an upstandingtubular extension 4 preferably integral with the base and whichextension has a radial tubular arm 5. A seat 6 for a check valve 7 isprovided at the lower end of the tubular extension 4 and another seat 8for a check valve 9 is provided at the inner end of the tubular arm 5. Anipple 10 is detachably mounted in the outer end of the arm 5 forengagement with a flexible tube a portion of which has been shown at 11,and which tube is adapted to be attached to the tire to be inflated. Anipple 12 is detachably connected to the upper end of the extension 4and is engaged by one end of a flexible tube 13. The other end of thistube 13 engages a nipple 11 extending clownwardly from a cap 15 in whichis formed a radial passage 16 which opens into the nipple 1d and alsoopens into a socket 17 receiving one end of a cylinder 18. The other endof this cylinder is closed as at 19 and slides within a tubular guide 20upstanding from a wing.21 which extends laterally from the upper head 22of a cylinder 23. This cylinder 23 is mounted at its through a port 24into the radial passage 3. The base 1 is secured to the head 22 by rods25 and slidably mounted within the head 22 and concentric with. thecylinder 23 is a piston rod 26 to the lower end of which is attached apiston 27 designed to reciprocate within the cylinder 23. The upper endof the rod 26 is attached to a handle 28 which may be ofany desiredshape so as to be readily grasped by the user. A U-shaped piston rod 29is secured at one end to the handle 28 and extends downwardly through aguide opening 30 in the wing 21 and parallel with the cylinder 23. Saidrod then extends upwardly through an opening 31 in the head 19 and isprovided with a piston 32 designed to work within the cylinder 18, thispiston being arranged oppositely to the piston 27 ,and the two pistonsbeing so positioned that when the piston 27 is moving downwardly toexpel air from the cylinder ,23, the piston 32 is moving downwardly torecharge the cylinder 18.

Guide straps 33 are designed to embrace the parallel portions of theU-shaped piston rod 29 and to engage the cylinder 23 and one of theguide rods 25, these straps constituting guides for the rod 29 so as tohold it against displacement during the operation of the pump.

As shown in the drawings, the upper cylinder 18 is of much less diameterthan the lower or main cylinder 23.

When the pump is not in use, the upper or secondary cylinder 18 ispushed downwardly in the guide 20 so as to be supported at one side ofthe main cylinder 23 and with piston 32 located in the upper portion ofcylinder 18, while the piston 27 is located in the lower portion ofcylinder 23.

lowerend within the socket 2 and discharges In using the pump theflexible tube 11 is attached to the tire to be inflated and the handle28 is drawn upwardly in the usual manner. This will cause the piston 27to move upwardly within the cylinder 23 and to charge the lower portionof the cylinder with air supplied through one or more openings in thehead 22. At the same time the piston 32 will thrust upwardly against thecap 15 and cause the cylinder 18 to slide upwardly to the upper limit ofits movement. During the reverse or downward stroke of the piston 27 theair in the path of said piston will be expelled through the passage 3into the extension 4: and the pressure will be equalized within the tireand within the upper cylinder 18 by a portion of this air passingoutwardly into the tube 11 and upwardly through the tube13. The

pressure will be retained in the tire and in the upper cylinder 18 bythe check valves 9 and 7 respectively, the pressure thus maintained inthe cylinder 18 serving to hold said cylinder in its elevated position.When the pistons are moved upwardly on the next stroke the lower portionof the cylinder 23 will be recharged while the piston 32 will moveupwardly and expel the air in the upper portion of cylinder 18, causingthis air to unseat the valve 9 and flow into the tire. During the nextor down stroke of the pistons the air in the path of the piston 27 willagain be directed into the extension and will first flow upwardly intothe cylinder 18 where it will be compressed until the pressure of airwithin said cylinder 18 is equal to the pressure of air within the tire,whereupon an additional supply of air will be directed into the tire sothat the pressure in the tire and the upper cylinder 18 will beequalized. This operation is continued during the reciprocation of thepistons and it has been found that a very eiiicient pump is producedbecause no leakage can take place through glands such as ordinarilyprovided in the path of air under pressure and because of the storedpressure constantly maintained within the cylinder 18. The cylinder 18will always act as a cushion to receive excessive pressure and thispressure will subsequently be distributed to the tire if greater thanthat within the tire.

lVhen the pump is not in use, the supplemental cylinder can be pusheddownwardly to the position shown in Fig. 1 so that the pump can thus bestored in a small space.

The straps 38 constitute eiiicient guides for the piston rod 29 and areca able of sliding along the cylinder 23 anc one of the rods :25.

That is claimed is z- 1. A pump including a. main cylinder, a secondarycylinder slidably mounted at one side of and parallel with the maincylinder,

a flexible tubular connection between the outlet of the main cylinderand the inlet of the secondary cylinder, a piston mounted forreciprocation in the main cylinder, a piston mounted for reciprocationin the secondary cylinder, an actuating handle, a piston rod connectingthe handle to the piston in the main cylinder, a U-shaped piston rodconnecting the handle to the piston in the secondary cylinder, a valvedoutlet in communication with both cylinders, and a check valveinterposed between said outlet'and the outlet of the main cylinder.

2. A pump includinga main cylinder having a valved outlet, at smallersecondary cylinder slidably mounted and parallel with the main cylinder,a connection between said valved outlet and the inletof the secondarycylinder, said connection including a flexible tubular portion, a valvedoutlet extending from said connection, a piston mounted within eachcylinder, ahandle portion, and rods connecting said handle portion tothe respective pistons to move the pistons in unison during theactuationof the handle portion. r

3. A pump including a main cylinder having a valvedout-let,a'smallersecondary cylinder slidably mounted and parallel with the maincylinder, a connection between said valved outlet and the inlet of thesecondary cylinder, said connection including a flexible tubularportion, a valved outlet extending from said connection, apiston mountedwithin each cylinder, a handle portion, and rods connecting said handleportion to the respective pistons to move the pistons in unison duringthe actuationof the handle portion, saidpistons being oppositelydisposed to successively expel'the' contents of their respectivecylinders.

41. In a pump the combination with a base having a socket therein, andanoutlet extension in communication with the socket, there being a checkvalve within said extension, of a cylinder seated at one end in thesocket and in communication with the outlet, a head on the cylinder andhaving a guide wing extending-therefrom, means for attaching the headtothe base, a secondary cylinder; mounted to slide within the-guide wingand having an outlet cap at itsupper end, a flexible tubularconnection'between said cap and the tubular outlet of the first namedcylinder, pistons mounted to reciprocate within the respectivecylinders, means for moving said pistons in unison, and a valved outletin communication with the outlet of the secondary cylinder.

5. The combination with a main cylinder having a valved outlet, a guideupon the main cylinder, and a secondary cylinder adapted to slide withint-heguide and having an outlet at its upper-end, of a flexible tubularconnection between said outlets, a

valved outlet extending from said connection, a piston within eachcylinder, a handle portion, and rods connecting said handle portion tothe respective cylinders.

6. The combination with a main cylinder having a valved outlet, a guideupon the main cylinder, and a secondary cylinder adapted to slide withinthe guide and having an outlet at its upper end, of a flexible tubularconnection between said outlets, a valved outlet extending from saidconnec tion, a piston within each cylinder, a handle portion, and rodsconnecting said handle portion to the respective cylinders, one of saidrods being U-sliaped and movable along the outer side of the maincylinder.

7. The combination with a main cylinder having a valved outlet, a guideupon the main cylinder, and a secondary cylinder adapted to slide withinthe guide and having an outlet at its upper end, of a flexible tubularconnection between said outlets, a valved outlet extending from saidconnection, a piston within each cylinder, a handle portion, rodsconnecting said handle portion to the respective cylinders, one of saidrods being U-shaped and movable along the outer side of the maincylinder, and a guide slidably engaging the main cylinder and connectedto the U-shaped rod.

In testimony that I claim the foregoing as my own, I have hereto affixedmy signature in the presence of two witnesses.

JOHN K. TOMLINSON.

Witnesses:

IRY E. SIMPSON, PHILOMENA A. RooxELLI.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

